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  26 <div class="titlepage"><div><div><h3 class="title">
  27 <a name="boost_asio.reference.buffer_cast"></a><a class="link" href="buffer_cast.html" title="buffer_cast">buffer_cast</a>
  28 </h3></div></div></div>
  29 <p>
  30         <a class="indexterm" name="idp159811664"></a>
  31 The <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">buffer_cast</span></code> function is used to obtain
  32         a pointer to the underlying memory region associated with a buffer.
  33       </p>
  34 <pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span>
  35     <span class="keyword">typename</span> <span class="identifier">PointerToPodType</span><span class="special">&gt;</span>
  36 <span class="identifier">PointerToPodType</span> <a class="link" href="buffer_cast/overload1.html" title="buffer_cast (1 of 2 overloads)">buffer_cast</a><span class="special">(</span>
  37     <span class="keyword">const</span> <span class="identifier">mutable_buffer</span> <span class="special">&amp;</span> <span class="identifier">b</span><span class="special">);</span>
  38   <span class="emphasis"><em>&#187; <a class="link" href="buffer_cast/overload1.html" title="buffer_cast (1 of 2 overloads)">more...</a></em></span>
  39
  40 <span class="keyword">template</span><span class="special">&lt;</span>
  41     <span class="keyword">typename</span> <span class="identifier">PointerToPodType</span><span class="special">&gt;</span>
  42 <span class="identifier">PointerToPodType</span> <a class="link" href="buffer_cast/overload2.html" title="buffer_cast (2 of 2 overloads)">buffer_cast</a><span class="special">(</span>
  43     <span class="keyword">const</span> <span class="identifier">const_buffer</span> <span class="special">&amp;</span> <span class="identifier">b</span><span class="special">);</span>
  44   <span class="emphasis"><em>&#187; <a class="link" href="buffer_cast/overload2.html" title="buffer_cast (2 of 2 overloads)">more...</a></em></span>
  45 </pre>
  46 <h5>
  47 <a name="boost_asio.reference.buffer_cast.h0"></a>
  48         <span class="phrase"><a name="boost_asio.reference.buffer_cast.examples_"></a></span><a class="link" href="buffer_cast.html#boost_asio.reference.buffer_cast.examples_">Examples:</a>
  49       </h5>
  50 <p>
  51         To access the memory of a non-modifiable buffer, use:
  52       </p>
  53 <pre class="programlisting"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">const_buffer</span> <span class="identifier">b1</span> <span class="special">=</span> <span class="special">...;</span>
  54 <span class="keyword">const</span> <span class="keyword">unsigned</span> <span class="keyword">char</span><span class="special">*</span> <span class="identifier">p1</span> <span class="special">=</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">buffer_cast</span><span class="special">&lt;</span><span class="keyword">const</span> <span class="keyword">unsigned</span> <span class="keyword">char</span><span class="special">*&gt;(</span><span class="identifier">b1</span><span class="special">);</span>
  55 </pre>
  56 <p>
  57         To access the memory of a modifiable buffer, use:
  58       </p>
  59 <pre class="programlisting"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">mutable_buffer</span> <span class="identifier">b2</span> <span class="special">=</span> <span class="special">...;</span>
  60 <span class="keyword">unsigned</span> <span class="keyword">char</span><span class="special">*</span> <span class="identifier">p2</span> <span class="special">=</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">buffer_cast</span><span class="special">&lt;</span><span class="keyword">unsigned</span> <span class="keyword">char</span><span class="special">*&gt;(</span><span class="identifier">b2</span><span class="special">);</span>
  61 </pre>
  62 <p>
  63         The <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">buffer_cast</span></code> function permits violations
  64         of type safety, so uses of it in application code should be carefully considered.
  65       </p>
  66 <h5>
  67 <a name="boost_asio.reference.buffer_cast.h1"></a>
  68         <span class="phrase"><a name="boost_asio.reference.buffer_cast.requirements"></a></span><a class="link" href="buffer_cast.html#boost_asio.reference.buffer_cast.requirements">Requirements</a>
  69       </h5>
  70 <p>
  71         <span class="emphasis"><em>Header: </em></span><code class="literal">boost/asio/buffer.hpp</code>
  72       </p>
  73 <p>
  74         <span class="emphasis"><em>Convenience header: </em></span><code class="literal">boost/asio.hpp</code>
  75       </p>
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  79 <td align="right"><div class="copyright-footer">Copyright &#169; 2003-2014 Christopher M. Kohlhoff<p>
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